Notes Payable and Borrowings under Capital Leases - Components of Company's Notes Payable and Borrowings under Capital Leases Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Debt And Capital Lease Obligations [Abstract]
Notes payable under credit facility	$ 509,688	$ 544,875
Capital leases	137	275
Less current portion	(20,272)	(20,738)
Notes payable and borrowings under capital leases, less current portion	$ 489,553	$ 524,412

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

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-Publisher SEC

-Name Regulation S-X (SX)

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-Section 03

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- References

No definition available.

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- Definition

Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Staff Accounting Bulletin (SAB)

-Number Topic 6

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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- Definition

Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

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-Publisher FASB

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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